https://www.khanacademy.org/science/ms-biology/x0c5bb03129646fd6:cells-and-organisms/x0c5bb03129646fd6:sensory-processing-and-the-brain/v/ms-sensory-processing-and-the-brain 2022-09-10T03:04:58.582913383Z Sensory processing and the brain Each sense receptor responds to different inputs (electromagnetic, mechanical, chemical), transmitting them as signals that travel along nerve cells to the brain. The signals are then processed in the brain, resulting in immediate behaviors or memories. Khan Academy video https://cdn.kastatic.org/ka_thumbnails_cache/da21a908-aa8b-49a5-b29c-541e4dc7a85c_1280_720_base.png Sensory processing and the brain Each sense receptor responds to different inputs (electromagnetic, mechanical, chemical), transmitting them as signals that travel along nerve cells to the brain. The signals are then processed in the brain, resulting in immediate behaviors or memories. https://cdn.kastatic.org/ka-youtube-converted/fMrz3L9bMsI.mp4/fMrz3L9bMsI.mp4 259 Mammalian sense organs https://www.khanacademy.org/science/health-and-medicine/nervous-system-and-sensory-infor/sight-vision/v/vision-structure-of-the-eye 2024-02-09T21:30:53.441494697Z The structure of the eye The eye's structure includes the sclera, cornea, conjunctiva, aqueous humour, lens, ciliary body, iris, pupil, vitreous humour, retina, optic nerve, choroid, fovea, and macula. These parts work together to capture light and convert it into images. The cornea and lens bend light, the iris controls light intake, and the retina transforms light into neural signals for the brain. Ronald Sahyouni video https://cdn.kastatic.org/googleusercontent/xxiqiXnezqBKN67fQiIbZuNBBmlxJDDFxSmqVoBLPBV6FVyN9rcm8m4luA3z7r-SuezVtS2LJiobRcSG44hbreqkAA The structure of the eye The eye's structure includes the sclera, cornea, conjunctiva, aqueous humour, lens, ciliary body, iris, pupil, vitreous humour, retina, optic nerve, choroid, fovea, and macula. These parts work together to capture light and convert it into images. The cornea and lens bend light, the iris controls light intake, and the retina transforms light into neural signals for the brain. https://cdn.kastatic.org/ka-youtube-converted/cTZl2qnzifc.mp4/cTZl2qnzifc.mp4 628 Mammalian sense organs https://www.khanacademy.org/science/cambridge-o-level-biology-cie/x2a084a90105205d2:coordination-and-control/x2a084a90105205d2:mammalian-sense-organs/v/human-eye-pk 2025-12-18T00:30:56.558401705Z Human eye Created by Khan Academy video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Human eye Created by Khan Academy https://cdn.kastatic.org/ka-youtube-converted/0AOeXHOQFDw.mp4/0AOeXHOQFDw.mp4 622 Mammalian sense organs https://www.khanacademy.org/science/health-and-medicine/nervous-system-and-sensory-infor/sight-vision/v/photoreceptor-distribution-fovea 2024-02-09T21:30:53.441494697Z Photoreceptor distribution in the fovea The human eye has a unique layout of rods and cones. Rods, mostly found in the eye's periphery, detect light and dark. Cones, concentrated in the fovea, recognize color. The fovea's design allows light to directly hit cones, enhancing resolution. The blind spot lacks photoreceptors as the optic nerve exits here. Ronald Sahyouni video https://cdn.kastatic.org/googleusercontent/-6ookXxDFrOL6RQsp_Rj1tv6BeF_Rd-l6T07rZjWnHB1l8NMjIER6LwpxupbTf-LZrGNb-dvf9Uf9fw6VFvNEiAZkw Photoreceptor distribution in the fovea The human eye has a unique layout of rods and cones. Rods, mostly found in the eye's periphery, detect light and dark. Cones, concentrated in the fovea, recognize color. The fovea's design allows light to directly hit cones, enhancing resolution. The blind spot lacks photoreceptors as the optic nerve exits here. https://cdn.kastatic.org/ka-youtube-converted/UXIfzc1UH-g.mp4/UXIfzc1UH-g.mp4 343 Mammalian sense organs https://www.khanacademy.org/science/cambridge-o-level-biology-cie/x2a084a90105205d2:coordination-and-control/x2a084a90105205d2:mammalian-sense-organs/v/human-eye-accommodation-and-near-point-pk 2025-12-18T00:30:56.558401705Z Human eye: accommodation and near point Created by Khan Academy video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Human eye: accommodation and near point Created by Khan Academy https://cdn.kastatic.org/ka-youtube-converted/ftGx30kzk4s.mp4/ftGx30kzk4s.mp4 592 Mammalian sense organs https://www.khanacademy.org/science/ms-biology/x0c5bb03129646fd6:cells-and-organisms/x0c5bb03129646fd6:sensory-processing-and-the-brain/a/sensory-processing-and-the-brain 2026-04-22T04:30:43.362363602Z Key points: Sensory processing and the brain Review your understanding of sensory processing and the brain in this free article aligned to NGSS standards. article https://www.khanacademy.org/science/cambridge-o-level-biology-cie/x2a084a90105205d2:coordination-and-control/x2a084a90105205d2:mammalian-sense-organs/e/functioning-of-the-eye 2026-04-07T22:23:57.656416987Z Functioning of the eye Explore how the human eye functions—how light forms images on the retina, how the lens focuses, and how the iris controls brightness. Learn about rods, cones, the fovea, and the blind spot through reasoning-based questions linking eye structure to clear, colourful vision. Yajurva Joshi exercise https://www.khanacademy.org/science/cambridge-o-level-biology-cie/x2a084a90105205d2:coordination-and-control/x2a084a90105205d2:mammalian-sense-organs/e/power-of-accommodation-in 2025-03-30T13:01:39.012708499Z Power of accommodation Let's solve some questions! vibhor exercise https://www.khanacademy.org/science/ms-biology/x0c5bb03129646fd6:cells-and-organisms/x0c5bb03129646fd6:sensory-processing-and-the-brain/e/understand-sensory-processing-and-the-brain 2026-02-27T20:00:43.673916617Z Understand: sensory processing and the brain Check your understanding of sensory processing and the brain in this set of free practice questions aligned to NGSS standards. Khan Academy exercise https://www.khanacademy.org/science/cambridge-o-level-biology-cie/x2a084a90105205d2:coordination-and-control/x2a084a90105205d2:mammalian-sense-organs/e/parts-of-the-human-eye---features-and-functions 2026-04-08T00:16:02.937952483Z Parts of the human eye - features and functions Let's practice identifying the features and functions of different parts of the human eye. Satrajit exercise https://www.khanacademy.org/science/cambridge-o-level-biology-cie/x2a084a90105205d2:coordination-and-control/x2a084a90105205d2:mammalian-sense-organs/e/parts-of-the-human-eye---labelling- 2026-04-08T01:15:04.085520103Z Parts of the human eye - labelling Let's practice labelling the different parts of the human eye. Satrajit exercise